coronal hole


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coronal hole

[kə′rō·nəl ‚hōl]
(astronomy)
A large-scale, apparently open structure in the solar corona, devoid of any soft x-ray emission and surrounded by diverging boundary structures.
References in periodicals archive ?
Last night's aurora was driven by a fast solar wind coming from a coronal hole.
1]) from the chromosphere and the corona (12) Region Quiet Sun Coronal hole Coronal temperature [K] 1.
Another coronal hole high speed stream caused a minor geomagnetic storm on Feb.
A coronal hole is an area where high-speed solar wind streams into space.
Washington, Oct 16 ( ANI ): Researchers have found evidence that magnetic waves in a polar coronal hole contain enough energy to heat the corona and that they also deposit most of their energy at sufficiently low heights for the heat to spread throughout the corona.
Similar low-speed winds have been identified from the CAT analysis of our IPS observations over the pole at solar maximum, when the polar coronal hole shrinks in size before and after its disappearance.
Hahn's team also calculated that the energy dissipated could provide up to 70% of that needed to heat the polar coronal hole and accelerate the fast solar wind.
The aurora seen on 2013 Aug 04/05 was the result of a coronal hole high speed stream with the IMF producing a southerly Bz with a strength of -13nT.
Washington, July 20 ( ANI ): European Space Agency/NASA Solar and Heliospheric Observatory, or SOHO, captured images of a gigantic coronal hole hovering over the Sun's north pole on July 18.
In the image, one coronal hole appears near the top center of the sun while another one – a polar coronal hole – is visible near the bottom of the view", space.